1. Field of the Invention
The present invention relates to a fastening device intended for retaining the heel of a ski boot on a ski. For this purpose, it comprises a plate adapted to be engaged by the heel of the ski boot, said plate being rotatably mounted about a mounting member rigid with the ski, and provided with means for retaining the rear portion of the ski boot.
However, this device is designed with a view to prevent ski flexions occurring when skiing between bumps, from compressing the boot sole between the toe-end binding device engaging the toe end of the sole and the heel hold-down means provided on said rotary plate. For this purpose, the rotary plate is mounted on the mounting plate rigid with the ski with a certain longitudinal lost motion, a spring being interposed between these two components. Thus, in case of ski flexion, the rotary plate supporting the boot heel can move somewhat in the longitudinal direction. However, under normal skiing conditions the boot is safely maintained between the toe device and the heel hold-down means carried by the rotary plate. In fact, the rotary plate is constantly urged forwardly by the return spring interposed between the rotary plate and the mounting plate rigid with the ski.
When positioning the boot heel on the rotary plate of the device according to this invention, this rotary plate should preferably be kept in its normal skiing position, so that the heel retaining means is disposed at the rear. For this purpose, a lock bolt adapted to be operated manually may be provided for holding the rotary plate against movement in its normal position. However, this lock bolt should subsequently be restored to a retracted or inoperative position to permit the free rotational movements of the rotary plate. This movement of the lock bolt to its retracted position may be controlled if desired by the means provided for retaining the heel on the plate when the heel is brought to its proper or skiing position thereon. This solution involves a special arrangement of said means. Besides, before engaging the boot in position, the user must actuate the lock bolt after having brought the rotary plate to its normal position.
2. Description of the Invention
It is the essential object of this invention to provide conditions such as to keep initially the rotary plate in this normal position without resorting to a lock bolt to be actuated manually by the user. For this purpose, there is provided between the rotary plate and the mounting member rigid with the ski a detent positioning device capable of holding the rotary plate in its normal angular position, the arrangement being such that this detent-positioning device is rendered inoperative when said plate is moved to the rear against the force of a return spring.
Now, this backward movement takes place automatically when positioning the boot since, to perfectly hold the boot against movement on the ski, a light pressure must be exerted between the toe device and the heel hold-down device of the ski binding. Thus, the detent positioning device is rendered automatically inoperative to permit the free pivotal movement of the rotary plate.
Other features and adavantages of the device according to this invention will appear as the following description proceeds with reference to the attached drawing given by way of illustration, not of limitation.